Optional Chaining

Optional Chaining ?.¶

?. propagates nil without NPE:

struct Address { city: str? }
struct User { address: Address? }

let user = User { address: nil }
let city = user.address?.city ?? "Unknown"
print(city) // Unknown — no error!

Goal: Create a User with nil address and get the city using optional chaining.

lesson-5-3.zolo

Program output

Run the code to see the output